Search Results

Search found 158 results on 7 pages for 'throttling'.

Page 7/7 | < Previous Page | 3 4 5 6 7 

• Meet the New Windows Azure

  - by ScottGu

  Today we are releasing a major set of improvements to Windows Azure.  Below is a short-summary of just a few of them: New Admin Portal and Command Line Tools Today’s release comes with a new Windows Azure portal that will enable you to manage all features and services offered on Windows Azure in a seamless, integrated way.  It is very fast and fluid, supports filtering and sorting (making it much easier to use for large deployments), works on all browsers, and offers a lot of great new features – including built-in VM, Web site, Storage, and Cloud Service monitoring support. The new portal is built on top of a REST-based management API within Windows Azure – and everything you can do through the portal can also be programmed directly against this Web API. We are also today releasing command-line tools (which like the portal call the REST Management APIs) to make it even easier to script and automate your administration tasks.  We are offering both a Powershell (for Windows) and Bash (for Mac and Linux) set of tools to download.  Like our SDKs, the code for these tools is hosted on GitHub under an Apache 2 license. Virtual Machines Windows Azure now supports the ability to deploy and run durable VMs in the cloud.  You can easily create these VMs using a new Image Gallery built-into the new Windows Azure Portal, or alternatively upload and run your own custom-built VHD images. Virtual Machines are durable (meaning anything you install within them persists across reboots) and you can use any OS with them.  Our built-in image gallery includes both Windows Server images (including the new Windows Server 2012 RC) as well as Linux images (including Ubuntu, CentOS, and SUSE distributions).  Once you create a VM instance you can easily Terminal Server or SSH into it in order to configure and customize the VM however you want (and optionally capture your own image snapshot of it to use when creating new VM instances).  This provides you with the flexibility to run pretty much any workload within Windows Azure.   The new Windows Azure Portal provides a rich set of management features for Virtual Machines – including the ability to monitor and track resource utilization within them.  Our new Virtual Machine support also enables the ability to easily attach multiple data-disks to VMs (which you can then mount and format as drives).  You can optionally enable geo-replication support on these – which will cause Windows Azure to continuously replicate your storage to a secondary data-center at least 400 miles away from your primary data-center as a backup. We use the same VHD format that is supported with Windows virtualization today (and which we’ve released as an open spec), which enables you to easily migrate existing workloads you might already have virtualized into Windows Azure.  We also make it easy to download VHDs from Windows Azure, which also provides the flexibility to easily migrate cloud-based VM workloads to an on-premise environment.  All you need to do is download the VHD file and boot it up locally, no import/export steps required. Web Sites Windows Azure now supports the ability to quickly and easily deploy ASP.NET, Node.js and PHP web-sites to a highly scalable cloud environment that allows you to start small (and for free) and then scale up as your traffic grows.  You can create a new web site in Azure and have it ready to deploy to in under 10 seconds: The new Windows Azure Portal provides built-in administration support for Web sites – including the ability to monitor and track resource utilization in real-time: You can deploy to web-sites in seconds using FTP, Git, TFS and Web Deploy.  We are also releasing tooling updates today for both Visual Studio and Web Matrix that enable developers to seamlessly deploy ASP.NET applications to this new offering.  The VS and Web Matrix publishing support includes the ability to deploy SQL databases as part of web site deployment – as well as the ability to incrementally update database schema with a later deployment. You can integrate web application publishing with source control by selecting the “Set up TFS publishing” or “Set up Git publishing” links on a web-site’s dashboard: Doing do will enable integration with our new TFS online service (which enables a full TFS workflow – including elastic build and testing support), or create a Git repository that you can reference as a remote and push deployments to.  Once you push a deployment using TFS or Git, the deployments tab will keep track of the deployments you make, and enable you to select an older (or newer) deployment and quickly redeploy your site to that snapshot of the code.  This provides a very powerful DevOps workflow experience.   Windows Azure now allows you to deploy up to 10 web-sites into a free, shared/multi-tenant hosting environment (where a site you deploy will be one of multiple sites running on a shared set of server resources).  This provides an easy way to get started on projects at no cost. You can then optionally upgrade your sites to run in a “reserved mode” that isolates them so that you are the only customer within a virtual machine: And you can elastically scale the amount of resources your sites use – allowing you to increase your reserved instance capacity as your traffic scales: Windows Azure automatically handles load balancing traffic across VM instances, and you get the same, super fast, deployment options (FTP, Git, TFS and Web Deploy) regardless of how many reserved instances you use. With Windows Azure you pay for compute capacity on a per-hour basis – which allows you to scale up and down your resources to match only what you need. Cloud Services and Distributed Caching Windows Azure also supports the ability to build cloud services that support rich multi-tier architectures, automated application management, and scale to extremely large deployments.  Previously we referred to this capability as “hosted services” – with this week’s release we are now referring to this capability as “cloud services”.  We are also enabling a bunch of new features with them. Distributed Cache One of the really cool new features being enabled with cloud services is a new distributed cache capability that enables you to use and setup a low-latency, in-memory distributed cache within your applications.  This cache is isolated for use just by your applications, and does not have any throttling limits. This cache can dynamically grow and shrink elastically (without you have to redeploy your app or make code changes), and supports the full richness of the AppFabric Cache Server API (including regions, high availability, notifications, local cache and more).  In addition to supporting the AppFabric Cache Server API, it also now supports the Memcached protocol – allowing you to point code written against Memcached at it (no code changes required). The new distributed cache can be setup to run in one of two ways: 1) Using a co-located approach.  In this option you allocate a percentage of memory in your existing web and worker roles to be used by the cache, and then the cache joins the memory into one large distributed cache.  Any data put into the cache by one role instance can be accessed by other role instances in your application – regardless of whether the cached data is stored on it or another role.  The big benefit with the “co-located” option is that it is free (you don’t have to pay anything to enable it) and it allows you to use what might have been otherwise unused memory within your application VMs. 2) Alternatively, you can add “cache worker roles” to your cloud service that are used solely for caching.  These will also be joined into one large distributed cache ring that other roles within your application can access.  You can use these roles to cache 10s or 100s of GBs of data in-memory very effectively – and the cache can be elastically increased or decreased at runtime within your application: New SDKs and Tooling Support We have updated all of the Windows Azure SDKs with today’s release to include new features and capabilities.  Our SDKs are now available for multiple languages, and all of the source in them is published under an Apache 2 license and and maintained in GitHub repositories. The .NET SDK for Azure has in particular seen a bunch of great improvements with today’s release, and now includes tooling support for both VS 2010 and the VS 2012 RC. We are also now shipping Windows, Mac and Linux SDK downloads for languages that are offered on all of these systems – allowing developers to develop Windows Azure applications using any development operating system. Much, Much More The above is just a short list of some of the improvements that are shipping in either preview or final form today – there is a LOT more in today’s release.  These include new Virtual Private Networking capabilities, new Service Bus runtime and tooling support, the public preview of the new Azure Media Services, new Data Centers, significantly upgraded network and storage hardware, SQL Reporting Services, new Identity features, support within 40+ new countries and territories, and much, much more. You can learn more about Windows Azure and sign-up to try it for free at http://windowsazure.com.  You can also watch a live keynote I’m giving at 1pm June 7th (later today) where I’ll walk through all of the new features.  We will be opening up the new features I discussed above for public usage a few hours after the keynote concludes.  We are really excited to see the great applications you build with them. Hope this helps, Scott

  Read the article

• Faster, Simpler access to Azure Tables with Enzo Azure API

  - by Herve Roggero

  After developing the latest version of Enzo Cloud Backup I took the time to create an API that would simplify access to Azure Tables (the Enzo Azure API). At first, my goal was to make the code simpler compared to the Microsoft Azure SDK. But as it turns out it is also a little faster; and when using the specialized methods (the fetch strategies) it is much faster out of the box than the Microsoft SDK, unless you start creating complex parallel and resilient routines yourself. Last but not least, I decided to add a few extension methods that I think you will find attractive, such as the ability to transform a list of entities into a DataTable. So let’s review each area in more details. Simpler Code My first objective was to make the API much easier to use than the Azure SDK. I wanted to reduce the amount of code necessary to fetch entities, remove the code needed to add automatic retries and handle transient conditions, and give additional control, such as a way to cancel operations, obtain basic statistics on the calls, and control the maximum number of REST calls the API generates in an attempt to avoid throttling conditions in the first place (something you cannot do with the Azure SDK at this time). Strongly Typed Before diving into the code, the following examples rely on a strongly typed class called MyData. The way MyData is defined for the Azure SDK is similar to the Enzo Azure API, with the exception that they inherit from different classes. With the Azure SDK, classes that represent entities must inherit from TableServiceEntity, while classes with the Enzo Azure API must inherit from BaseAzureTable or implement a specific interface. // With the SDK public class MyData1 : TableServiceEntity {     public string Message { get; set; }     public string Level { get; set; }     public string Severity { get; set; } } //  With the Enzo Azure API public class MyData2 : BaseAzureTable {     public string Message { get; set; }     public string Level { get; set; }     public string Severity { get; set; } } Simpler Code Now that the classes representing an Azure Table entity are defined, let’s review the methods that the Azure SDK would look like when fetching all the entities from an Azure Table (note the use of a few variables: the _tableName variable stores the name of the Azure Table, and the ConnectionString property returns the connection string for the Storage Account containing the table): // With the Azure SDK public List<MyData1> FetchAllEntities() {      CloudStorageAccount storageAccount = CloudStorageAccount.Parse(ConnectionString);      CloudTableClient tableClient = storageAccount.CreateCloudTableClient();      TableServiceContext serviceContext = tableClient.GetDataServiceContext();      CloudTableQuery<MyData1> partitionQuery =         (from e in serviceContext.CreateQuery<MyData1>(_tableName)         select new MyData1()         {            PartitionKey = e.PartitionKey,            RowKey = e.RowKey,            Timestamp = e.Timestamp,            Message = e.Message,            Level = e.Level,            Severity = e.Severity            }).AsTableServiceQuery<MyData1>();        return partitionQuery.ToList();  } This code gives you automatic retries because the AsTableServiceQuery does that for you. Also, note that this method is strongly-typed because it is using LINQ. Although this doesn’t look like too much code at first glance, you are actually mapping the strongly-typed object manually. So for larger entities, with dozens of properties, your code will grow. And from a maintenance standpoint, when a new property is added, you may need to change the mapping code. You will also note that the mapping being performed is optional; it is desired when you want to retrieve specific properties of the entities (not all) to reduce the network traffic. If you do not specify the properties you want, all the properties will be returned; in this example we are returning the Message, Level and Severity properties (in addition to the required PartitionKey, RowKey and Timestamp). The Enzo Azure API does the mapping automatically and also handles automatic reties when fetching entities. The equivalent code to fetch all the entities (with the same three properties) from the same Azure Table looks like this: // With the Enzo Azure API public List<MyData2> FetchAllEntities() {        AzureTable at = new AzureTable(_accountName, _accountKey, _ssl, _tableName);        List<MyData2> res = at.Fetch<MyData2>("", "Message,Level,Severity");        return res; } As you can see, the Enzo Azure API returns the entities already strongly typed, so there is no need to map the output. Also, the Enzo Azure API makes it easy to specify the list of properties to return, and to specify a filter as well (no filter was provided in this example; the filter is passed as the first parameter).  Fetch Strategies Both approaches discussed above fetch the data sequentially. In addition to the linear/sequential fetch methods, the Enzo Azure API provides specific fetch strategies. Fetch strategies are designed to prepare a set of REST calls, executed in parallel, in a way that performs faster that if you were to fetch the data sequentially. For example, if the PartitionKey is a GUID string, you could prepare multiple calls, providing appropriate filters ([‘a’, ‘b’[, [‘b’, ‘c’[, [‘c’, ‘d[, …), and send those calls in parallel. As you can imagine, the code necessary to create these requests would be fairly large. With the Enzo Azure API, two strategies are provided out of the box: the GUID and List strategies. If you are interested in how these strategies work, see the Enzo Azure API Online Help. Here is an example code that performs parallel requests using the GUID strategy (which executes more than 2 t o3 times faster than the sequential methods discussed previously): public List<MyData2> FetchAllEntitiesGUID() {     AzureTable at = new AzureTable(_accountName, _accountKey, _ssl, _tableName);     List<MyData2> res = at.FetchWithGuid<MyData2>("", "Message,Level,Severity");     return res; } Faster Results With Sequential Fetch Methods Developing a faster API wasn’t a primary objective; but it appears that the performance tests performed with the Enzo Azure API deliver the data a little faster out of the box (5%-10% on average, and sometimes to up 50% faster) with the sequential fetch methods. Although the amount of data is the same regardless of the approach (and the REST calls are almost exactly identical), the object mapping approach is different. So it is likely that the slight performance increase is due to a lighter API. Using LINQ offers many advantages and tremendous flexibility; nevertheless when fetching data it seems that the Enzo Azure API delivers faster.  For example, the same code previously discussed delivered the following results when fetching 3,000 entities (about 1KB each). The average elapsed time shows that the Azure SDK returned the 3000 entities in about 5.9 seconds on average, while the Enzo Azure API took 4.2 seconds on average (39% improvement). With Fetch Strategies When using the fetch strategies we are no longer comparing apples to apples; the Azure SDK is not designed to implement fetch strategies out of the box, so you would need to code the strategies yourself. Nevertheless I wanted to provide out of the box capabilities, and as a result you see a test that returned about 10,000 entities (1KB each entity), and an average execution time over 5 runs. The Azure SDK implemented a sequential fetch while the Enzo Azure API implemented the List fetch strategy. The fetch strategy was 2.3 times faster. Note that the following test hit a limit on my network bandwidth quickly (3.56Mbps), so the results of the fetch strategy is significantly below what it could be with a higher bandwidth. Additional Methods The API wouldn’t be complete without support for a few important methods other than the fetch methods discussed previously. The Enzo Azure API offers these additional capabilities: - Support for batch updates, deletes and inserts - Conversion of entities to DataRow, and List<> to a DataTable - Extension methods for Delete, Merge, Update, Insert - Support for asynchronous calls and cancellation - Support for fetch statistics (total bytes, total REST calls, retries…) For more information, visit http://www.bluesyntax.net or go directly to the Enzo Azure API page (http://www.bluesyntax.net/EnzoAzureAPI.aspx). About Herve Roggero Herve Roggero, Windows Azure MVP, is the founder of Blue Syntax Consulting, a company specialized in cloud computing products and services. Herve's experience includes software development, architecture, database administration and senior management with both global corporations and startup companies. Herve holds multiple certifications, including an MCDBA, MCSE, MCSD. He also holds a Master's degree in Business Administration from Indiana University. Herve is the co-author of "PRO SQL Azure" from Apress and runs the Azure Florida Association (on LinkedIn: http://www.linkedin.com/groups?gid=4177626). For more information on Blue Syntax Consulting, visit www.bluesyntax.net.

  Read the article

• CLSF & CLK 2013 Trip Report by Jeff Liu

  - by jamesmorris

  This is a contributed post from Jeff Liu, lead XFS developer for the Oracle mainline Linux kernel team. Recently, I attended both the China Linux Storage and Filesystem workshop (CLSF), and the China Linux Kernel conference (CLK), which were held in Shanghai. Here are the highlights for both events. CLSF - 17th October XFS update (led by Jeff Liu) XFS keeps rapid progress with a lot of changes, especially focused on the infrastructure/performance improvements as well as  new feature development.  This can be reflected with a sample statistics among XFS/Ext4+JBD2/Btrfs via: # git diff --stat --minimal -C -M v3.7..v3.12-rc4 -- fs/xfs|fs/ext4+fs/jbd2|fs/btrfs XFS: 141 files changed, 27598 insertions(+), 19113 deletions(-) Ext4+JBD2: 39 files changed, 10487 insertions(+), 5454 deletions(-) Btrfs: 70 files changed, 19875 insertions(+), 8130 deletions(-) What made up those changes in XFS? Self-describing metadata(CRC32c). This is a new feature and it contributed about 70% code changes, it can be enabled via `mkfs.xfs -m crc=1 /dev/xxx` for v5 superblock. Transaction log space reservation improvements. With this change, we can calculate the log space reservation at mount time rather than runtime to reduce the the CPU overhead. User namespace support. So both XFS and USERNS can be enabled on kernel configuration begin from Linux 3.10. Thanks Dwight Engen's efforts for this thing. Split project/group quota inodes. Originally, project quota can not be enabled with group quota at the same time because they were share the same quota file inode, now it works but only for v5 super block. i.e, CRC enabled. CONFIG_XFS_WARN, an new lightweight runtime debugger which can be deployed in production environment. Readahead log object recovery, this change can speed up the log replay progress significantly. Speculative preallocation inode tracking, clearing and throttling. The main purpose is to deal with inodes with post-EOF space due to speculative preallocation, support improved quota management to free up a significant amount of unwritten space when at or near EDQUOT. It support backgroup scanning which occurs on a longish interval(5 mins by default, tunable), and on-demand scanning/trimming via ioctl(2). Bitter arguments ensued from this session, especially for the comparison between Ext4 and Btrfs in different areas, I have to spent a whole morning of the 1st day answering those questions. We basically agreed on XFS is the best choice in Linux nowadays because: Stable, XFS has a good record in stability in the past 10 years. Fengguang Wu who lead the 0-day kernel test project also said that he has observed less error than other filesystems in the past 1+ years, I own it to the XFS upstream code reviewer, they always performing serious code review as well as testing. Good performance for large/small files, XFS does not works very well for small files has already been an old story for years. Best choice (maybe) for distributed PB filesystems. e.g, Ceph recommends delopy OSD daemon on XFS because Ext4 has limited xattr size. Best choice for large storage (>16TB). Ext4 does not support a single file more than around 15.95TB. Scalability, any objection to XFS is best in this point? :) XFS is better to deal with transaction concurrency than Ext4, why? The maximum size of the log in XFS is 2038MB compare to 128MB in Ext4. Misc. Ext4 is widely used and it has been proved fast/stable in various loads and scenarios, XFS just need more customers, and Btrfs is still on the road to be a manhood. Ceph Introduction (Led by Li Wang) This a hot topic.  Li gave us a nice introduction about the design as well as their current works. Actually, Ceph client has been included in Linux kernel since 2.6.34 and supported by Openstack since Folsom but it seems that it has not yet been widely deployment in production environment. Their major work is focus on the inline data support to separate the metadata and data storage, reduce the file access time, i.e, a file access need communication twice, fetch the metadata from MDS and then get data from OSD, and also, the small file access is limited by the network latency. The solution is, for the small files they would like to store the data at metadata so that when accessing a small file, the metadata server can push both metadata and data to the client at the same time. In this way, they can reduce the overhead of calculating the data offset and save the communication to OSD. For this feature, they have only run some small scale testing but really saw noticeable improvements. Test environment: Intel 2 CPU 12 Core, 64GB RAM, Ubuntu 12.04, Ceph 0.56.6 with 200GB SATA disk, 15 OSD, 1 MDS, 1 MON. The sequence read performance for 1K size files improved about 50%. I have asked Li and Zheng Yan (the core developer of Ceph, who also worked on Btrfs) whether Ceph is really stable and can be deployed at production environment for large scale PB level storage, but they can not give a positive answer, looks Ceph even does not spread over Dreamhost (subject to confirmation). From Li, they only deployed Ceph for a small scale storage(32 nodes) although they'd like to try 6000 nodes in the future. Improve Linux swap for Flash storage (led by Shaohua Li) Because of high density, low power and low price, flash storage (SSD) is a good candidate to partially replace DRAM. A quick answer for this is using SSD as swap. But Linux swap is designed for slow hard disk storage, so there are a lot of challenges to efficiently use SSD for swap. SWAPOUT swap_map scan swap_map is the in-memory data structure to track swap disk usage, but it is a slow linear scan. It will become a bottleneck while finding many adjacent pages in the use of SSD. Shaohua Li have changed it to a cluster(128K) list, resulting in O(1) algorithm. However, this apporoach needs restrictive cluster alignment and only enabled for SSD. IO pattern In most cases, the swap io is in interleaved pattern because of mutiple reclaimers or a free cluster is shared by all reclaimers. Even though block layer can merge interleaved IO to some extent, but we cannot count on it completely. Hence the per-cpu cluster is added base on the previous change, it can help reclaimer do sequential IO and the block layer will be easier to merge IO. TLB flush: If we're reclaiming one active page, we should first move the page from active lru list to inactive lru list, and then reclaim the page from inactive lru to swap it out. During the process, we need to clear PTE twice: first is 'A'(ACCESS) bit, second is 'P'(PRESENT) bit. Processors need to send lots of ipi which make the TLB flush really expensive. Some works have been done to improve this, including rework smp_call_functiom_many() or remove the first TLB flush in x86, but there still have some arguments here and only parts of works have been pushed to mainline. SWAPIN: Page fault does iodepth=1 sync io, but it's a little waste if only issue a page size's IO. The obvious solution is doing swap readahead. But the current in-kernel swap readahead is arbitary(always 8 pages), and it always doesn't perform well for both random and sequential access workload. Shaohua introduced a new flag for madvise(MADV_WILLNEED) to do swap prefetch, so the changes happen in userspace API and leave the in-kernel readahead unchanged(but I think some improvement can also be done here). SWAP discard As we know, discard is important for SSD write throughout, but the current swap discard implementation is synchronous. He changed it to async discard which allow discard and write run in the same time. Meanwhile, the unit of discard is also optimized to cluster. Misc: lock contention For many concurrent swapout and swapin , the lock contention such as anon_vma or swap_lock is high, so he changed the swap_lock to a per-swap lock. But there still have some lock contention in very high speed SSD because of swapcache address_space lock. Zproject (led by Bob Liu) Bob gave us a very nice introduction about the current memory compression status. Now there are 3 projects(zswap/zram/zcache) which all aim at smooth swap IO storm and promote performance, but they all have their own pros and cons. ZSWAP It is implemented based on frontswap API and it uses a dynamic allocater named Zbud to allocate free pages. Zbud means pairs of zpages are "buddied" and it can only store at most two compressed pages in one page frame, so the max compress ratio is 50%. Each page frame is lru-linked and can do shink in memory pressure. If the compressed memory pool reach its limitation, shink or reclaim happens. It decompress the page frame into two new allocated pages and then write them to real swap device, but it can fail when allocating the two pages. ZRAM Acts as a compressed ramdisk and used as swap device, and it use zsmalloc as its allocator which has high density but may have fragmentation issues. Besides, page reclaim is hard since it will need more pages to uncompress and free just one page. ZRAM is preferred by embedded system which may not have any real swap device. Now both ZRAM and ZSWAP are in driver/staging tree, and in the mm community there are some disscussions of merging ZRAM into ZSWAP or viceversa, but no agreement yet. ZCACHE Handles file page compression but it is removed out of staging recently. From industry (led by Tang Jie, LSI) An LSI engineer introduced several new produces to us. The first is raid5/6 cards that it use full stripe writes to improve performance. The 2nd one he introduced is SandForce flash controller, who can understand data file types (data entropy) to reduce write amplification (WA) for nearly all writes. It's called DuraWrite and typical WA is 0.5. What's more, if enable its Dynamic Logical Capacity function module, the controller can do data compression which is transparent to upper layer. LSI testing shows that with this virtual capacity enables 1x TB drive can support up to 2x TB capacity, but the application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion. He said the most useful application is for datebase. Another thing I think it's worth to mention is that a NV-DRAM memory in NMR/Raptor which is directly exposed to host system. Applications can directly access the NV-DRAM via a memory address - using standard system call mmap(). He said that it is very useful for database logging now. This kind of NVM produces are beginning to appear in recent years, and it is said that Samsung is building a research center in China for related produces. IMHO, NVM will bring an effect to current os layer especially on file system, e.g. its journaling may need to redesign to fully utilize these nonvolatile memory. OCFS2 (led by Canquan Shen) Without a doubt, HuaWei is the biggest contributor to OCFS2 in the past two years. They have posted 46 upstream patches and 39 patches have been merged. Their current project is based on 32/64 nodes cluster, but they also tried 128 nodes at the experimental stage. The major work they are working is to support ATS (atomic test and set), it can be works with DLM at the same time. Looks this idea is inspired by the vmware VMFS locking, i.e, http://blogs.vmware.com/vsphere/2012/05/vmfs-locking-uncovered.html CLK - 18th October 2013 Improving Linux Development with Better Tools (Andi Kleen) This talk focused on how to find/solve bugs along with the Linux complexity growing. Generally, we can do this with the following kind of tools: Static code checkers tools. e.g, sparse, smatch, coccinelle, clang checker, checkpatch, gcc -W/LTO, stanse. This can help check a lot of things, simple mistakes, complex problems, but the challenges are: some are very slow, false positives, may need a concentrated effort to get false positives down. Especially, no static checker I found can follow indirect calls (“OO in C”, common in kernel): struct foo_ops { int (*do_foo)(struct foo *obj); } foo->do_foo(foo); Dynamic runtime checkers, e.g, thread checkers, kmemcheck, lockdep. Ideally all kernel code would come with a test suite, then someone could run all the dynamic checkers. Fuzzers/test suites. e.g, Trinity is a great tool, it finds many bugs, but needs manual model for each syscall. Modern fuzzers around using automatic feedback, but notfor kernel yet: http://taviso.decsystem.org/making_software_dumber.pdf Debuggers/Tracers to understand code, e.g, ftrace, can dump on events/oops/custom triggers, but still too much overhead in many cases to run always during debug. Tools to read/understand source, e.g, grep/cscope work great for many cases, but do not understand indirect pointers (OO in C model used in kernel), give us all “do_foo” instances: struct foo_ops { int (*do_foo)(struct foo *obj); } = { .do_foo = my_foo }; foo>do_foo(foo); That would be great to have a cscope like tool that understands this based on types/initializers XFS: The High Performance Enterprise File System (Jeff Liu) [slides] I gave a talk for introducing the disk layout, unique features, as well as the recent changes.   The slides include some charts to reflect the performances between XFS/Btrfs/Ext4 for small files. About a dozen users raised their hands when I asking who has experienced with XFS. I remembered that when I asked the same question in LinuxCon/Japan, only 3 people raised their hands, but they are Chris Mason, Ric Wheeler, and another attendee. The attendee questions were mainly focused on stability, and comparison with other file systems. Linux Containers (Feng Gao) The speaker introduced us that the purpose for those kind of namespaces, include mount/UTS/IPC/Network/Pid/User, as well as the system API/ABI. For the userspace tools, He mainly focus on the Libvirt LXC rather than us(LXC). Libvirt LXC is another userspace container management tool, implemented as one type of libvirt driver, it can manage containers, create namespace, create private filesystem layout for container, Create devices for container and setup resources controller via cgroup. In this talk, Feng also mentioned another two possible new namespaces in the future, the 1st is the audit, but not sure if it should be assigned to user namespace or not. Another is about syslog, but the question is do we really need it? In-memory Compression (Bob Liu) Same as CLSF, a nice introduction that I have already mentioned above. Misc There were some other talks related to ACPI based memory hotplug, smart wake-affinity in scheduler etc., but my head is not big enough to record all those things. -- Jeff Liu

  Read the article

• ASPNET WebAPI REST Guidance

  - by JoshReuben

  ASP.NET Web API is an ideal platform for building RESTful applications on the .NET Framework. While I may be more partial to NodeJS these days, there is no denying that WebAPI is a well engineered framework. What follows is my investigation of how to leverage WebAPI to construct a RESTful frontend API.   The Advantages of REST Methodology over SOAP Simpler API for CRUD ops Standardize Development methodology - consistent and intuitive Standards based à client interop Wide industry adoption, Ease of use à easy to add new devs Avoid service method signature blowout Smaller payloads than SOAP Stateless à no session data means multi-tenant scalability Cache-ability Testability   General RESTful API Design Overview · utilize HTTP Protocol - Usage of HTTP methods for CRUD, standard HTTP response codes, common HTTP headers and Mime Types · Resources are mapped to URLs, actions are mapped to verbs and the rest goes in the headers. · keep the API semantic, resource-centric – A RESTful, resource-oriented service exposes a URI for every piece of data the client might want to operate on. A REST-RPC Hybrid exposes a URI for every operation the client might perform: one URI to fetch a piece of data, a different URI to delete that same data. utilize Uri to specify CRUD op, version, language, output format: http://api.MyApp.com/{ver}/{lang}/{resource_type}/{resource_id}.{output_format}?{key&filters} · entity CRUD operations are matched to HTTP methods: · Create - POST / PUT · Read – GET - cacheable · Update – PUT · Delete - DELETE · Use Uris to represent a hierarchies - Resources in RESTful URLs are often chained · Statelessness allows for idempotency – apply an op multiple times without changing the result. POST is non-idempotent, the rest are idempotent (if DELETE flags records instead of deleting them). · Cache indication - Leverage HTTP headers to label cacheable content and indicate the permitted duration of cache · PUT vs POST - The client uses PUT when it determines which URI (Id key) the new resource should have. The client uses POST when the server determines they key. PUT takes a second param – the id. POST creates a new resource. The server assigns the URI for the new object and returns this URI as part of the response message. Note: The PUT method replaces the entire entity. That is, the client is expected to send a complete representation of the updated product. If you want to support partial updates, the PATCH method is preferred DELETE deletes a resource at a specified URI – typically takes an id param · Leverage Common HTTP Response Codes in response headers 200 OK: Success 201 Created - Used on POST request when creating a new resource. 304 Not Modified: no new data to return. 400 Bad Request: Invalid Request. 401 Unauthorized: Authentication. 403 Forbidden: Authorization 404 Not Found – entity does not exist. 406 Not Acceptable – bad params. 409 Conflict - For POST / PUT requests if the resource already exists. 500 Internal Server Error 503 Service Unavailable · Leverage uncommon HTTP Verbs to reduce payload sizes HEAD - retrieves just the resource meta-information. OPTIONS returns the actions supported for the specified resource. PATCH - partial modification of a resource. · When using PUT, POST or PATCH, send the data as a document in the body of the request. Don't use query parameters to alter state. · Utilize Headers for content negotiation, caching, authorization, throttling o Content Negotiation – choose representation (e.g. JSON or XML and version), language & compression. Signal via RequestHeader.Accept & ResponseHeader.Content-Type Accept: application/json;version=1.0 Accept-Language: en-US Accept-Charset: UTF-8 Accept-Encoding: gzip o Caching - ResponseHeader: Expires (absolute expiry time) or Cache-Control (relative expiry time) o Authorization - basic HTTP authentication uses the RequestHeader.Authorization to specify a base64 encoded string "username:password". can be used in combination with SSL/TLS (HTTPS) and leverage OAuth2 3rd party token-claims authorization. Authorization: Basic sQJlaTp5ZWFslylnaNZ= o Rate Limiting - Not currently part of HTTP so specify non-standard headers prefixed with X- in the ResponseHeader. X-RateLimit-Limit: 10000 X-RateLimit-Remaining: 9990 · HATEOAS Methodology - Hypermedia As The Engine Of Application State – leverage API as a state machine where resources are states and the transitions between states are links between resources and are included in their representation (hypermedia) – get API metadata signatures from the response Link header - in a truly REST based architecture any URL, except the initial URL, can be changed, even to other servers, without worrying about the client. · error responses - Do not just send back a 200 OK with every response. Response should consist of HTTP error status code (JQuery has automated support for this), A human readable message , A Link to a meaningful state transition , & the original data payload that was problematic. · the URIs will typically map to a server-side controller and a method name specified by the type of request method. Stuff all your calls into just four methods is not as crazy as it sounds. · Scoping - Path variables look like you’re traversing a hierarchy, and query variables look like you’re passing arguments into an algorithm · Mapping URIs to Controllers - have one controller for each resource is not a rule – can consolidate - route requests to the appropriate controller and action method · Keep URls Consistent - Sometimes it’s tempting to just shorten our URIs. not recommend this as this can cause confusion · Join Naming – for m-m entity relations there may be multiple hierarchy traversal paths · Routing – useful level of indirection for versioning, server backend mocking in development ASPNET WebAPI Considerations ASPNET WebAPI implements a lot (but not all) RESTful API design considerations as part of its infrastructure and via its coding convention. Overview When developing an API there are basically three main steps: 1. Plan out your URIs 2. Setup return values and response codes for your URIs 3. Implement a framework for your API.   Design · Leverage Models MVC folder · Repositories – support IoC for tests, abstraction · Create DTO classes – a level of indirection decouples & allows swap out · Self links can be generated using the UrlHelper · Use IQueryable to support projections across the wire · Models can support restful navigation properties – ICollection<T> · async mechanism for long running ops - return a response with a ticket – the client can then poll or be pushed the final result later. · Design for testability - Test using HttpClient , JQuery ( $.getJSON , $.each) , fiddler, browser debug. Leverage IDependencyResolver – IoC wrapper for mocking · Easy debugging - IE F12 developer tools: Network tab, Request Headers tab     Routing · HTTP request method is matched to the method name. (This rule applies only to GET, POST, PUT, and DELETE requests.) · {id}, if present, is matched to a method parameter named id. · Query parameters are matched to parameter names when possible · Done in config via Routes.MapHttpRoute – similar to MVC routing · Can alternatively: o decorate controller action methods with HttpDelete, HttpGet, HttpHead,HttpOptions, HttpPatch, HttpPost, or HttpPut., + the ActionAttribute o use AcceptVerbsAttribute to support other HTTP verbs: e.g. PATCH, HEAD o use NonActionAttribute to prevent a method from getting invoked as an action · route table Uris can support placeholders (via curly braces{}) – these can support default values and constraints, and optional values · The framework selects the first route in the route table that matches the URI. Response customization · Response code: By default, the Web API framework sets the response status code to 200 (OK). But according to the HTTP/1.1 protocol, when a POST request results in the creation of a resource, the server should reply with status 201 (Created). Non Get methods should return HttpResponseMessage · Location: When the server creates a resource, it should include the URI of the new resource in the Location header of the response. public HttpResponseMessage PostProduct(Product item) {     item = repository.Add(item);     var response = Request.CreateResponse<Product>(HttpStatusCode.Created, item);     string uri = Url.Link("DefaultApi", new { id = item.Id });     response.Headers.Location = new Uri(uri);     return response; } Validation · Decorate Models / DTOs with System.ComponentModel.DataAnnotations properties RequiredAttribute, RangeAttribute. · Check payloads using ModelState.IsValid · Under posting – leave out values in JSON payload à JSON formatter assigns a default value. Use with RequiredAttribute · Over-posting - if model has RO properties à use DTO instead of model · Can hook into pipeline by deriving from ActionFilterAttribute & overriding OnActionExecuting Config · Done in App_Start folder > WebApiConfig.cs – static Register method: HttpConfiguration param: The HttpConfiguration object contains the following members. Member Description DependencyResolver Enables dependency injection for controllers. Filters Action filters – e.g. exception filters. Formatters Media-type formatters. by default contains JsonFormatter, XmlFormatter IncludeErrorDetailPolicy Specifies whether the server should include error details, such as exception messages and stack traces, in HTTP response messages. Initializer A function that performs final initialization of the HttpConfiguration. MessageHandlers HTTP message handlers - plug into pipeline ParameterBindingRules A collection of rules for binding parameters on controller actions. Properties A generic property bag. Routes The collection of routes. Services The collection of services. · Configure JsonFormatter for circular references to support links: PreserveReferencesHandling.Objects Documentation generation · create a help page for a web API, by using the ApiExplorer class. · The ApiExplorer class provides descriptive information about the APIs exposed by a web API as an ApiDescription collection · create the help page as an MVC view public ILookup<string, ApiDescription> GetApis()         {             return _explorer.ApiDescriptions.ToLookup(                 api => api.ActionDescriptor.ControllerDescriptor.ControllerName); · provide documentation for your APIs by implementing the IDocumentationProvider interface. Documentation strings can come from any source that you like – e.g. extract XML comments or define custom attributes to apply to the controller [ApiDoc("Gets a product by ID.")] [ApiParameterDoc("id", "The ID of the product.")] public HttpResponseMessage Get(int id) · GlobalConfiguration.Configuration.Services – add the documentation Provider · To hide an API from the ApiExplorer, add the ApiExplorerSettingsAttribute Plugging into the Message Handler pipeline · Plug into request / response pipeline – derive from DelegatingHandler and override theSendAsync method – e.g. for logging error codes, adding a custom response header · Can be applied globally or to a specific route Exception Handling · Throw HttpResponseException on method failures – specify HttpStatusCode enum value – examine this enum, as its values map well to typical op problems · Exception filters – derive from ExceptionFilterAttribute & override OnException. Apply on Controller or action methods, or add to global HttpConfiguration.Filters collection · HttpError object provides a consistent way to return error information in the HttpResponseException response body. · For model validation, you can pass the model state to CreateErrorResponse, to include the validation errors in the response public HttpResponseMessage PostProduct(Product item) {     if (!ModelState.IsValid)     {         return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState); Cookie Management · Cookie header in request and Set-Cookie headers in a response - Collection of CookieState objects · Specify Expiry, max-age resp.Headers.AddCookies(new CookieHeaderValue[] { cookie }); Internet Media Types, formatters and serialization · Defaults to application/json · Request Accept header and response Content-Type header · determines how Web API serializes and deserializes the HTTP message body. There is built-in support for XML, JSON, and form-urlencoded data · customizable formatters can be inserted into the pipeline · POCO serialization is opt out via JsonIgnoreAttribute, or use DataMemberAttribute for optin · JSON serializer leverages NewtonSoft Json.NET · loosely structured JSON objects are serialzed as JObject which derives from Dynamic · to handle circular references in json: json.SerializerSettings.PreserveReferencesHandling =    PreserveReferencesHandling.All à {"$ref":"1"}. · To preserve object references in XML [DataContract(IsReference=true)] · Content negotiation Accept: Which media types are acceptable for the response, such as “application/json,” “application/xml,” or a custom media type such as "application/vnd.example+xml" Accept-Charset: Which character sets are acceptable, such as UTF-8 or ISO 8859-1. Accept-Encoding: Which content encodings are acceptable, such as gzip. Accept-Language: The preferred natural language, such as “en-us”. o Web API uses the Accept and Accept-Charset headers. (At this time, there is no built-in support for Accept-Encoding or Accept-Language.) · Controller methods can take JSON representations of DTOs as params – auto-deserialization · Typical JQuery GET request: function find() {     var id = $('#prodId').val();     $.getJSON("api/products/" + id,         function (data) {             var str = data.Name + ': $' + data.Price;             $('#product').text(str);         })     .fail(         function (jqXHR, textStatus, err) {             $('#product').text('Error: ' + err);         }); }            · Typical GET response: HTTP/1.1 200 OK Server: ASP.NET Development Server/10.0.0.0 Date: Mon, 18 Jun 2012 04:30:33 GMT X-AspNet-Version: 4.0.30319 Cache-Control: no-cache Pragma: no-cache Expires: -1 Content-Type: application/json; charset=utf-8 Content-Length: 175 Connection: Close [{"Id":1,"Name":"TomatoSoup","Price":1.39,"ActualCost":0.99},{"Id":2,"Name":"Hammer", "Price":16.99,"ActualCost":10.00},{"Id":3,"Name":"Yo yo","Price":6.99,"ActualCost": 2.05}] True OData support · Leverage Query Options $filter, $orderby, $top and $skip to shape the results of controller actions annotated with the [Queryable]attribute. [Queryable]  public IQueryable<Supplier> GetSuppliers()  · Query: ~/Suppliers?$filter=Name eq ‘Microsoft’ · Applies the following selection filter on the server: GetSuppliers().Where(s => s.Name == “Microsoft”)  · Will pass the result to the formatter. · true support for the OData format is still limited - no support for creates, updates, deletes, $metadata and code generation etc · vnext: ability to configure how EditLinks, SelfLinks and Ids are generated Self Hosting no dependency on ASPNET or IIS: using (var server = new HttpSelfHostServer(config)) {     server.OpenAsync().Wait(); Tracing · tracability tools, metrics – e.g. send to nagios · use your choice of tracing/logging library, whether that is ETW,NLog, log4net, or simply System.Diagnostics.Trace. · To collect traces, implement the ITraceWriter interface public class SimpleTracer : ITraceWriter {     public void Trace(HttpRequestMessage request, string category, TraceLevel level,         Action<TraceRecord> traceAction)     {         TraceRecord rec = new TraceRecord(request, category, level);         traceAction(rec);         WriteTrace(rec); · register the service with config · programmatically trace – has helper extension methods: Configuration.Services.GetTraceWriter().Info( · Performance tracing - pipeline writes traces at the beginning and end of an operation - TraceRecord class includes aTimeStamp property, Kind property set to TraceKind.Begin / End Security · Roles class methods: RoleExists, AddUserToRole · WebSecurity class methods: UserExists, .CreateUserAndAccount · Request.IsAuthenticated · Leverage HTTP 401 (Unauthorized) response · [AuthorizeAttribute(Roles="Administrator")] – can be applied to Controller or its action methods · See section in WebApi document on "Claim-based-security for ASP.NET Web APIs using DotNetOpenAuth" – adapt this to STS.--> Web API Host exposes secured Web APIs which can only be accessed by presenting a valid token issued by the trusted issuer. http://zamd.net/2012/05/04/claim-based-security-for-asp-net-web-apis-using-dotnetopenauth/ · Use MVC membership provider infrastructure and add a DelegatingHandler child class to the WebAPI pipeline - http://stackoverflow.com/questions/11535075/asp-net-mvc-4-web-api-authentication-with-membership-provider - this will perform the login actions · Then use AuthorizeAttribute on controllers and methods for role mapping- http://sixgun.wordpress.com/2012/02/29/asp-net-web-api-basic-authentication/ · Alternate option here is to rely on MVC App : http://forums.asp.net/t/1831767.aspx/1

  Read the article

• Why does Mac OS X Software Update not work when machine uses Active Directory?

  - by Lyndsey Ferguson

  My company's IT department is mostly a Windows run operation and in order to become more secure, they are altering the way that the Macintosh computers login to our internal network so that they use Active Directory like their Windows counterparts. I have been given Administrative permission on my Mac and I am able to do most of what I used to be able to do in terms of authentication of software installations. However, there is a problem: the "Software Update" feature doesn't work. What happens is that when I try to get the Mac to perform its Software Updates from the Apple menu, the normal window appears listing what has to be updated; I am able to select what to update and click the "Update" button, but then nothing happens. It doesn't ask for authentication like it used to, the computer doesn't perform any download or installation (it does sometimes ask me to agree to license agreements for iTunes). I can download the updates individually and install them without any issues, but the auto-update fails. I'd rather use the Software Update menu item like I used to: it is much more convenient. Any suggestions on how I can fix this? EDIT Nov 19th, 2009, 10:09 EST: I have posted this question to the Apple Mac OS X Snow Leopard support forum. EDIT Nov 19th, 2009, 12:39 EST:Yes, the Terminal command "sudo softwareupdate --install --all" does work flawlessly. I want to avoid that as my co-workers are generally not comfortable on the Mac. I also tried Chealion's suggestion to delete "~/Library/Preferences/com.apple.SoftwareUpdate.plist" and "/Library/Preferences/com.apple.SoftwareUpdate.plist", Software Update still fails. However, I did get diagnostic messages in the Console (below). I've deleted the MS Office Package Receipts and examined the suhelperd (Software Update Helper Daemon?); it appears that suhelperd is crashing and that explains why it doesn't work. I've submitted a bug report to Apple (radar://7408619). Here are the Console diagnostic messages: 11/19/09 12:36:44 PM com.apple.suhelperd[66829] terminate called after throwing an instance of 'NSException' 11/19/09 12:36:47 PM com.apple.launchd[1] (com.apple.suhelperd[66829]) Job appears to have crashed: Abort trap 11/19/09 12:36:48 PM com.apple.ReportCrash.Root[66830] 2009-11-19 12:36:48.275 ReportCrash[66830:2703] Saved crash report for suhelperd[66829] version ??? (???) to /Library/Logs/DiagnosticReports/suhelperd_2009-11-19-123648_localhost.crash 11/19/09 12:36:54 PM com.apple.launchd[1] (com.apple.suhelperd) Throttling respawn: Will start in 1 seconds 11/19/09 12:36:55 PM com.apple.suhelperd[66836] terminate called after throwing an instance of 'NSException' 11/19/09 12:36:55 PM com.apple.launchd[1] (com.apple.suhelperd[66836]) Job appears to have crashed: Abort trap 11/19/09 12:36:56 PM com.apple.ReportCrash.Root[66830] 2009-11-19 12:36:56.017 ReportCrash[66830:2f03] Saved crash report for suhelperd[66836] version ??? (???) to /Library/Logs/DiagnosticReports/suhelperd_2009-11-19-123655_localhost.crash 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_automator.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_automator_workflow.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_autoupdate.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_clipart.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_core.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_dock.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_entourage.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_entourage_help_std.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_equationeditor.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_errorreporting.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_excel.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_excel_help_std.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_fonts.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_graph.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_helpviewer.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_launch.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_ooxml.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_orgchart.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_powerpoint.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_powerpoint_help_std.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_brazilian.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_danish.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_dutch.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_english.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_finnish.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_french.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_german.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_italian.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_japanese.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_norwegian.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_portuguese.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_spanish.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_proofing_swedish.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_required.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_silverlight.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_sounds.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_word.pkg 11/19/09 12:36:58 PM Software Update[66826] PackageKit: *** Missing bundle identifier: /Library/Receipts/Office2008_en_word_help_std.pkg 11/19/09 12:37:26 PM com.apple.suhelperd[66839] terminate called after throwing an instance of 'NSException' 11/19/09 12:37:26 PM com.apple.launchd[1] (com.apple.suhelperd[66839]) Job appears to have crashed: Abort trap 11/19/09 12:37:26 PM com.apple.ReportCrash.Root[66830] 2009-11-19 12:37:26.929 ReportCrash[66830:2b07] Saved crash report for suhelperd[66839] version ??? (???) to /Library/Logs/DiagnosticReports/suhelperd_2009-11-19-123726_localhost.crash And here is the suhelperd crash report: Process: suhelperd [66839] Path: /System/Library/PrivateFrameworks/SoftwareUpdate.framework/Versions/A/Resources/suhelperd Identifier: suhelperd Version: ??? (???) Code Type: X86-64 (Native) Parent Process: launchd [1] Date/Time: 2009-11-19 12:37:26.473 -0500 OS Version: Mac OS X 10.6.2 (10C540) Report Version: 6 Exception Type: EXC_CRASH (SIGABRT) Exception Codes: 0x0000000000000000, 0x0000000000000000 Crashed Thread: 0 Dispatch queue: com.apple.main-thread Application Specific Information: abort() called *** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[NSCFArray objectAtIndex:]: index (0) beyond bounds (0)' *** Call stack at first throw: ( 0 CoreFoundation 0x00007fff859a9444 __exceptionPreprocess + 180 1 libobjc.A.dylib 0x00007fff8787e0f3 objc_exception_throw + 45 2 CoreFoundation 0x00007fff859a9267 +[NSException raise:format:arguments:] + 103 3 CoreFoundation 0x00007fff859a91f4 +[NSException raise:format:] + 148 4 Foundation 0x00007fff855da080 _NSArrayRaiseBoundException + 122 5 Foundation 0x00007fff8553cb81 -[NSCFArray objectAtIndex:] + 75 6 Admin 0x00007fff8107920e +[User(UserPrivate) _userWithInfo:attributes:] + 71 7 Admin 0x00007fff81080d6b +[User findUserByID:searchParent:] + 404 8 suhelperd 0x0000000100001274 0x0 + 4294972020 9 suhelperd 0x0000000100002240 0x0 + 4294976064 10 suhelperd 0x00000001000053b1 0x0 + 4294988721 11 suhelperd 0x00000001000044b3 0x0 + 4294984883 12 suhelperd 0x0000000100004154 0x0 + 4294984020 13 libSystem.B.dylib 0x00007fff83eb60d8 mach_msg_server + 357 14 suhelperd 0x00000001000036eb 0x0 + 4294981355 15 suhelperd 0x0000000100002a1f 0x0 + 4294978079 16 suhelperd 0x0000000100001080 0x0 + 4294971520 ) Thread 0 Crashed: Dispatch queue: com.apple.main-thread 0 libSystem.B.dylib 0x00007fff83e86fe6 __kill + 10 1 libSystem.B.dylib 0x00007fff83f27e32 abort + 83 2 libstdc++.6.dylib 0x00007fff873cf5d2 __tcf_0 + 0 3 libobjc.A.dylib 0x00007fff87881d29 _objc_terminate + 100 4 libstdc++.6.dylib 0x00007fff873cdae1 __cxxabiv1::__terminate(void (*)()) + 11 5 libstdc++.6.dylib 0x00007fff873cdb16 __cxxabiv1::__unexpected(void (*)()) + 0 6 libstdc++.6.dylib 0x00007fff873cdbfc __gxx_exception_cleanup(_Unwind_Reason_Code, _Unwind_Exception*) + 0 7 libobjc.A.dylib 0x00007fff8787e192 object_getIvar + 0 8 com.apple.CoreFoundation 0x00007fff859a9267 +[NSException raise:format:arguments:] + 103 9 com.apple.CoreFoundation 0x00007fff859a91f4 +[NSException raise:format:] + 148 10 com.apple.Foundation 0x00007fff855da080 _NSArrayRaiseBoundException + 122 11 com.apple.Foundation 0x00007fff8553cb81 -[NSCFArray objectAtIndex:] + 75 12 com.apple.framework.Admin 0x00007fff8107920e +[User(UserPrivate) _userWithInfo:attributes:] + 71 13 com.apple.framework.Admin 0x00007fff81080d6b +[User findUserByID:searchParent:] + 404 14 suhelperd 0x0000000100001274 0x100000000 + 4724 15 suhelperd 0x0000000100002240 0x100000000 + 8768 16 suhelperd 0x00000001000053b1 0x100000000 + 21425 17 suhelperd 0x00000001000044b3 0x100000000 + 17587 18 suhelperd 0x0000000100004154 0x100000000 + 16724 19 libSystem.B.dylib 0x00007fff83eb60d8 mach_msg_server + 357 20 suhelperd 0x00000001000036eb 0x100000000 + 14059 21 suhelperd 0x0000000100002a1f 0x100000000 + 10783 22 suhelperd 0x0000000100001080 0x100000000 + 4224 Thread 1: Dispatch queue: com.apple.libdispatch-manager 0 libSystem.B.dylib 0x00007fff83e51bba kevent + 10 1 libSystem.B.dylib 0x00007fff83e53a85 _dispatch_mgr_invoke + 154 2 libSystem.B.dylib 0x00007fff83e5375c _dispatch_queue_invoke + 185 3 libSystem.B.dylib 0x00007fff83e53286 _dispatch_worker_thread2 + 244 4 libSystem.B.dylib 0x00007fff83e52bb8 _pthread_wqthread + 353 5 libSystem.B.dylib 0x00007fff83e52a55 start_wqthread + 13 Thread 2: 0 libSystem.B.dylib 0x00007fff83e529da __workq_kernreturn + 10 1 libSystem.B.dylib 0x00007fff83e52dec _pthread_wqthread + 917 2 libSystem.B.dylib 0x00007fff83e52a55 start_wqthread + 13 Thread 0 crashed with X86 Thread State (64-bit): rax: 0x0000000000000000 rbx: 0x00007fff707d7298 rcx: 0x00007fff5fbff868 rdx: 0x0000000000000000 rdi: 0x0000000000010517 rsi: 0x0000000000000006 rbp: 0x00007fff5fbff880 rsp: 0x00007fff5fbff868 r8: 0x00007fff707da9e0 r9: 0x0000000000000063 r10: 0x00007fff83e83026 r11: 0x0000000000000202 r12: 0x00007fff85a2dca1 r13: 0x0000000000000000 r14: 0x00007fff70bea228 r15: 0x00007fff5fbffb10 rip: 0x00007fff83e86fe6 rfl: 0x0000000000000202 cr2: 0x00007fff70e3afd0

  Read the article

• Help with Collision Resolution?

  - by Milo

  I'm trying to learn about physics by trying to make a simplified GTA 2 clone. My only problem is collision resolution. Everything else works great. I have a rigid body class and from there cars and a wheel class: class RigidBody extends Entity { //linear private Vector2D velocity = new Vector2D(); private Vector2D forces = new Vector2D(); private OBB2D predictionRect = new OBB2D(new Vector2D(), 1.0f, 1.0f, 0.0f); private float mass; private Vector2D deltaVec = new Vector2D(); private Vector2D v = new Vector2D(); //angular private float angularVelocity; private float torque; private float inertia; //graphical private Vector2D halfSize = new Vector2D(); private Bitmap image; private Matrix mat = new Matrix(); private float[] Vector2Ds = new float[2]; private Vector2D tangent = new Vector2D(); private static Vector2D worldRelVec = new Vector2D(); private static Vector2D relWorldVec = new Vector2D(); private static Vector2D pointVelVec = new Vector2D(); public RigidBody() { //set these defaults so we don't get divide by zeros mass = 1.0f; inertia = 1.0f; setLayer(LAYER_OBJECTS); } protected void rectChanged() { if(getWorld() != null) { getWorld().updateDynamic(this); } } //intialize out parameters public void initialize(Vector2D halfSize, float mass, Bitmap bitmap) { //store physical parameters this.halfSize = halfSize; this.mass = mass; image = bitmap; inertia = (1.0f / 20.0f) * (halfSize.x * halfSize.x) * (halfSize.y * halfSize.y) * mass; RectF rect = new RectF(); float scalar = 10.0f; rect.left = (int)-halfSize.x * scalar; rect.top = (int)-halfSize.y * scalar; rect.right = rect.left + (int)(halfSize.x * 2.0f * scalar); rect.bottom = rect.top + (int)(halfSize.y * 2.0f * scalar); setRect(rect); predictionRect.set(rect); } public void setLocation(Vector2D position, float angle) { getRect().set(position, getWidth(), getHeight(), angle); rectChanged(); } public void setPredictionLocation(Vector2D position, float angle) { getPredictionRect().set(position, getWidth(), getHeight(), angle); } public void setPredictionCenter(Vector2D center) { getPredictionRect().moveTo(center); } public void setPredictionAngle(float angle) { predictionRect.setAngle(angle); } public Vector2D getPosition() { return getRect().getCenter(); } public OBB2D getPredictionRect() { return predictionRect; } @Override public void update(float timeStep) { doUpdate(false,timeStep); } public void doUpdate(boolean prediction, float timeStep) { //integrate physics //linear Vector2D acceleration = Vector2D.scalarDivide(forces, mass); if(prediction) { Vector2D velocity = Vector2D.add(this.velocity, Vector2D.scalarMultiply(acceleration, timeStep)); Vector2D c = getRect().getCenter(); c = Vector2D.add(getRect().getCenter(), Vector2D.scalarMultiply(velocity , timeStep)); setPredictionCenter(c); //forces = new Vector2D(0,0); //clear forces } else { velocity.x += (acceleration.x * timeStep); velocity.y += (acceleration.y * timeStep); //velocity = Vector2D.add(velocity, Vector2D.scalarMultiply(acceleration, timeStep)); Vector2D c = getRect().getCenter(); v.x = getRect().getCenter().getX() + (velocity.x * timeStep); v.y = getRect().getCenter().getY() + (velocity.y * timeStep); deltaVec.x = v.x - c.x; deltaVec.y = v.y - c.y; deltaVec.normalize(); setCenter(v.x, v.y); forces.x = 0; //clear forces forces.y = 0; } //angular float angAcc = torque / inertia; if(prediction) { float angularVelocity = this.angularVelocity + angAcc * timeStep; setPredictionAngle(getAngle() + angularVelocity * timeStep); //torque = 0; //clear torque } else { angularVelocity += angAcc * timeStep; setAngle(getAngle() + angularVelocity * timeStep); torque = 0; //clear torque } } public void updatePrediction(float timeStep) { doUpdate(true, timeStep); } //take a relative Vector2D and make it a world Vector2D public Vector2D relativeToWorld(Vector2D relative) { mat.reset(); Vector2Ds[0] = relative.x; Vector2Ds[1] = relative.y; mat.postRotate(JMath.radToDeg(getAngle())); mat.mapVectors(Vector2Ds); relWorldVec.x = Vector2Ds[0]; relWorldVec.y = Vector2Ds[1]; return new Vector2D(Vector2Ds[0], Vector2Ds[1]); } //take a world Vector2D and make it a relative Vector2D public Vector2D worldToRelative(Vector2D world) { mat.reset(); Vector2Ds[0] = world.x; Vector2Ds[1] = world.y; mat.postRotate(JMath.radToDeg(-getAngle())); mat.mapVectors(Vector2Ds); return new Vector2D(Vector2Ds[0], Vector2Ds[1]); } //velocity of a point on body public Vector2D pointVelocity(Vector2D worldOffset) { tangent.x = -worldOffset.y; tangent.y = worldOffset.x; return Vector2D.add( Vector2D.scalarMultiply(tangent, angularVelocity) , velocity); } public void applyForce(Vector2D worldForce, Vector2D worldOffset) { //add linear force forces.x += worldForce.x; forces.y += worldForce.y; //add associated torque torque += Vector2D.cross(worldOffset, worldForce); } @Override public void draw( GraphicsContext c) { c.drawRotatedScaledBitmap(image, getPosition().x, getPosition().y, getWidth(), getHeight(), getAngle()); } public Vector2D getVelocity() { return velocity; } public void setVelocity(Vector2D velocity) { this.velocity = velocity; } public Vector2D getDeltaVec() { return deltaVec; } } Vehicle public class Wheel { private Vector2D forwardVec; private Vector2D sideVec; private float wheelTorque; private float wheelSpeed; private float wheelInertia; private float wheelRadius; private Vector2D position = new Vector2D(); public Wheel(Vector2D position, float radius) { this.position = position; setSteeringAngle(0); wheelSpeed = 0; wheelRadius = radius; wheelInertia = (radius * radius) * 1.1f; } public void setSteeringAngle(float newAngle) { Matrix mat = new Matrix(); float []vecArray = new float[4]; //forward Vector vecArray[0] = 0; vecArray[1] = 1; //side Vector vecArray[2] = -1; vecArray[3] = 0; mat.postRotate(newAngle / (float)Math.PI * 180.0f); mat.mapVectors(vecArray); forwardVec = new Vector2D(vecArray[0], vecArray[1]); sideVec = new Vector2D(vecArray[2], vecArray[3]); } public void addTransmissionTorque(float newValue) { wheelTorque += newValue; } public float getWheelSpeed() { return wheelSpeed; } public Vector2D getAnchorPoint() { return position; } public Vector2D calculateForce(Vector2D relativeGroundSpeed, float timeStep, boolean prediction) { //calculate speed of tire patch at ground Vector2D patchSpeed = Vector2D.scalarMultiply(Vector2D.scalarMultiply( Vector2D.negative(forwardVec), wheelSpeed), wheelRadius); //get velocity difference between ground and patch Vector2D velDifference = Vector2D.add(relativeGroundSpeed , patchSpeed); //project ground speed onto side axis Float forwardMag = new Float(0.0f); Vector2D sideVel = velDifference.project(sideVec); Vector2D forwardVel = velDifference.project(forwardVec, forwardMag); //calculate super fake friction forces //calculate response force Vector2D responseForce = Vector2D.scalarMultiply(Vector2D.negative(sideVel), 2.0f); responseForce = Vector2D.subtract(responseForce, forwardVel); float topSpeed = 500.0f; //calculate torque on wheel wheelTorque += forwardMag * wheelRadius; //integrate total torque into wheel wheelSpeed += wheelTorque / wheelInertia * timeStep; //top speed limit (kind of a hack) if(wheelSpeed > topSpeed) { wheelSpeed = topSpeed; } //clear our transmission torque accumulator wheelTorque = 0; //return force acting on body return responseForce; } public void setTransmissionTorque(float newValue) { wheelTorque = newValue; } public float getTransmissionTourque() { return wheelTorque; } public void setWheelSpeed(float speed) { wheelSpeed = speed; } } //our vehicle object public class Vehicle extends RigidBody { private Wheel [] wheels = new Wheel[4]; private boolean throttled = false; public void initialize(Vector2D halfSize, float mass, Bitmap bitmap) { //front wheels wheels[0] = new Wheel(new Vector2D(halfSize.x, halfSize.y), 0.45f); wheels[1] = new Wheel(new Vector2D(-halfSize.x, halfSize.y), 0.45f); //rear wheels wheels[2] = new Wheel(new Vector2D(halfSize.x, -halfSize.y), 0.75f); wheels[3] = new Wheel(new Vector2D(-halfSize.x, -halfSize.y), 0.75f); super.initialize(halfSize, mass, bitmap); } public void setSteering(float steering) { float steeringLock = 0.13f; //apply steering angle to front wheels wheels[0].setSteeringAngle(steering * steeringLock); wheels[1].setSteeringAngle(steering * steeringLock); } public void setThrottle(float throttle, boolean allWheel) { float torque = 85.0f; throttled = true; //apply transmission torque to back wheels if (allWheel) { wheels[0].addTransmissionTorque(throttle * torque); wheels[1].addTransmissionTorque(throttle * torque); } wheels[2].addTransmissionTorque(throttle * torque); wheels[3].addTransmissionTorque(throttle * torque); } public void setBrakes(float brakes) { float brakeTorque = 15.0f; //apply brake torque opposing wheel vel for (Wheel wheel : wheels) { float wheelVel = wheel.getWheelSpeed(); wheel.addTransmissionTorque(-wheelVel * brakeTorque * brakes); } } public void doUpdate(float timeStep, boolean prediction) { for (Wheel wheel : wheels) { float wheelVel = wheel.getWheelSpeed(); //apply negative force to naturally slow down car if(!throttled && !prediction) wheel.addTransmissionTorque(-wheelVel * 0.11f); Vector2D worldWheelOffset = relativeToWorld(wheel.getAnchorPoint()); Vector2D worldGroundVel = pointVelocity(worldWheelOffset); Vector2D relativeGroundSpeed = worldToRelative(worldGroundVel); Vector2D relativeResponseForce = wheel.calculateForce(relativeGroundSpeed, timeStep,prediction); Vector2D worldResponseForce = relativeToWorld(relativeResponseForce); applyForce(worldResponseForce, worldWheelOffset); } //no throttling yet this frame throttled = false; if(prediction) { super.updatePrediction(timeStep); } else { super.update(timeStep); } } @Override public void update(float timeStep) { doUpdate(timeStep,false); } public void updatePrediction(float timeStep) { doUpdate(timeStep,true); } public void inverseThrottle() { float scalar = 0.2f; for(Wheel wheel : wheels) { wheel.setTransmissionTorque(-wheel.getTransmissionTourque() * scalar); wheel.setWheelSpeed(-wheel.getWheelSpeed() * 0.1f); } } } And my big hack collision resolution: private void update() { camera.setPosition((vehicle.getPosition().x * camera.getScale()) - ((getWidth() ) / 2.0f), (vehicle.getPosition().y * camera.getScale()) - ((getHeight() ) / 2.0f)); //camera.move(input.getAnalogStick().getStickValueX() * 15.0f, input.getAnalogStick().getStickValueY() * 15.0f); if(input.isPressed(ControlButton.BUTTON_GAS)) { vehicle.setThrottle(1.0f, false); } if(input.isPressed(ControlButton.BUTTON_STEAL_CAR)) { vehicle.setThrottle(-1.0f, false); } if(input.isPressed(ControlButton.BUTTON_BRAKE)) { vehicle.setBrakes(1.0f); } vehicle.setSteering(input.getAnalogStick().getStickValueX()); //vehicle.update(16.6666666f / 1000.0f); boolean colided = false; vehicle.updatePrediction(16.66666f / 1000.0f); List<Entity> buildings = world.queryStaticSolid(vehicle,vehicle.getPredictionRect()); if(buildings.size() > 0) { colided = true; } if(!colided) { vehicle.update(16.66f / 1000.0f); } else { Vector2D delta = vehicle.getDeltaVec(); vehicle.setVelocity(Vector2D.negative(vehicle.getVelocity().multiply(0.2f)). add(delta.multiply(-1.0f))); vehicle.inverseThrottle(); } } Here is OBB public class OBB2D { // Corners of the box, where 0 is the lower left. private Vector2D corner[] = new Vector2D[4]; private Vector2D center = new Vector2D(); private Vector2D extents = new Vector2D(); private RectF boundingRect = new RectF(); private float angle; //Two edges of the box extended away from corner[0]. private Vector2D axis[] = new Vector2D[2]; private double origin[] = new double[2]; public OBB2D(Vector2D center, float w, float h, float angle) { set(center,w,h,angle); } public OBB2D(float left, float top, float width, float height) { set(new Vector2D(left + (width / 2), top + (height / 2)),width,height,0.0f); } public void set(Vector2D center,float w, float h,float angle) { Vector2D X = new Vector2D( (float)Math.cos(angle), (float)Math.sin(angle)); Vector2D Y = new Vector2D((float)-Math.sin(angle), (float)Math.cos(angle)); X = X.multiply( w / 2); Y = Y.multiply( h / 2); corner[0] = center.subtract(X).subtract(Y); corner[1] = center.add(X).subtract(Y); corner[2] = center.add(X).add(Y); corner[3] = center.subtract(X).add(Y); computeAxes(); extents.x = w / 2; extents.y = h / 2; computeDimensions(center,angle); } private void computeDimensions(Vector2D center,float angle) { this.center.x = center.x; this.center.y = center.y; this.angle = angle; boundingRect.left = Math.min(Math.min(corner[0].x, corner[3].x), Math.min(corner[1].x, corner[2].x)); boundingRect.top = Math.min(Math.min(corner[0].y, corner[1].y),Math.min(corner[2].y, corner[3].y)); boundingRect.right = Math.max(Math.max(corner[1].x, corner[2].x), Math.max(corner[0].x, corner[3].x)); boundingRect.bottom = Math.max(Math.max(corner[2].y, corner[3].y),Math.max(corner[0].y, corner[1].y)); } public void set(RectF rect) { set(new Vector2D(rect.centerX(),rect.centerY()),rect.width(),rect.height(),0.0f); } // Returns true if other overlaps one dimension of this. private boolean overlaps1Way(OBB2D other) { for (int a = 0; a < axis.length; ++a) { double t = other.corner[0].dot(axis[a]); // Find the extent of box 2 on axis a double tMin = t; double tMax = t; for (int c = 1; c < corner.length; ++c) { t = other.corner[c].dot(axis[a]); if (t < tMin) { tMin = t; } else if (t > tMax) { tMax = t; } } // We have to subtract off the origin // See if [tMin, tMax] intersects [0, 1] if ((tMin > 1 + origin[a]) || (tMax < origin[a])) { // There was no intersection along this dimension; // the boxes cannot possibly overlap. return false; } } // There was no dimension along which there is no intersection. // Therefore the boxes overlap. return true; } //Updates the axes after the corners move. Assumes the //corners actually form a rectangle. private void computeAxes() { axis[0] = corner[1].subtract(corner[0]); axis[1] = corner[3].subtract(corner[0]); // Make the length of each axis 1/edge length so we know any // dot product must be less than 1 to fall within the edge. for (int a = 0; a < axis.length; ++a) { axis[a] = axis[a].divide((axis[a].length() * axis[a].length())); origin[a] = corner[0].dot(axis[a]); } } public void moveTo(Vector2D center) { Vector2D centroid = (corner[0].add(corner[1]).add(corner[2]).add(corner[3])).divide(4.0f); Vector2D translation = center.subtract(centroid); for (int c = 0; c < 4; ++c) { corner[c] = corner[c].add(translation); } computeAxes(); computeDimensions(center,angle); } // Returns true if the intersection of the boxes is non-empty. public boolean overlaps(OBB2D other) { if(right() < other.left()) { return false; } if(bottom() < other.top()) { return false; } if(left() > other.right()) { return false; } if(top() > other.bottom()) { return false; } if(other.getAngle() == 0.0f && getAngle() == 0.0f) { return true; } return overlaps1Way(other) && other.overlaps1Way(this); } public Vector2D getCenter() { return center; } public float getWidth() { return extents.x * 2; } public float getHeight() { return extents.y * 2; } public void setAngle(float angle) { set(center,getWidth(),getHeight(),angle); } public float getAngle() { return angle; } public void setSize(float w,float h) { set(center,w,h,angle); } public float left() { return boundingRect.left; } public float right() { return boundingRect.right; } public float bottom() { return boundingRect.bottom; } public float top() { return boundingRect.top; } public RectF getBoundingRect() { return boundingRect; } public boolean overlaps(float left, float top, float right, float bottom) { if(right() < left) { return false; } if(bottom() < top) { return false; } if(left() > right) { return false; } if(top() > bottom) { return false; } return true; } }; What I do is when I predict a hit on the car, I force it back. It does not work that well and seems like a bad idea. What could I do to have more proper collision resolution. Such that if I hit a wall I will never get stuck in it and if I hit the side of a wall I can steer my way out of it. Thanks I found this nice ppt. It talks about pulling objects apart and calculating new velocities. How could I calc new velocities in my case? http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&ved=0CC8QFjAB&url=http%3A%2F%2Fcoitweb.uncc.edu%2F~tbarnes2%2FGameDesignFall05%2FSlides%2FCh4.2-CollDet.ppt&ei=x4ucULy5M6-N0QGRy4D4Cg&usg=AFQjCNG7FVDXWRdLv8_-T5qnFyYld53cTQ&cad=rja

  Read the article

• Frequent Disconnects ubuntu desktop 12.10 x64 intel 82579V e1000e

  - by user112055

  I'm having frequent disconnects with my new install of Ubuntu 12.10. I tried updating the kernel driver to the latest intel release to no avail. My expertise is spent. It happens anywhere between 1 min and 10 min. Any ideas? syslog: Dec 1 13:51:39 andromeda kernel: [ 972.188809] audit_printk_skb: 6 callbacks suppressed Dec 1 13:51:39 andromeda kernel: [ 972.188813] type=1701 audit(1354398699.418:199): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=4 compat=0 ip=0x7f26777d9205 code=0x50000 Dec 1 13:51:39 andromeda kernel: [ 972.188817] type=1701 audit(1354398699.418:200): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=4 compat=0 ip=0x7f26777d9205 code=0x50000 Dec 1 13:51:39 andromeda kernel: [ 972.188820] type=1701 audit(1354398699.418:201): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=4 compat=0 ip=0x7f26777d9205 code=0x50000 Dec 1 13:51:39 andromeda kernel: [ 972.188823] type=1701 audit(1354398699.418:202): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=4 compat=0 ip=0x7f26777d9205 code=0x50000 Dec 1 13:51:39 andromeda kernel: [ 972.188825] type=1701 audit(1354398699.418:203): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=4 compat=0 ip=0x7f26777d9205 code=0x50000 Dec 1 13:51:39 andromeda kernel: [ 972.331419] type=1701 audit(1354398699.558:204): auid=4294967295 uid=1000 gid=1000 ses=4294967295 pid=6039 comm="chrome" reason="seccomp" sig=0 syscall=2 compat=0 ip=0x7f26777d96b0 code=0x50000 Dec 1 13:53:12 andromeda NetworkManager[1115]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds) Dec 1 13:53:12 andromeda kernel: [ 1064.894387] e1000e: e1000e: eth0 NIC Link is Down Dec 1 13:53:16 andromeda NetworkManager[1115]: <info> (eth0): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40] Dec 1 13:53:16 andromeda NetworkManager[1115]: <info> (eth0): deactivating device (reason 'carrier-changed') [40] Dec 1 13:53:16 andromeda NetworkManager[1115]: <info> (eth0): canceled DHCP transaction, DHCP client pid 5946 Dec 1 13:53:16 andromeda avahi-daemon[890]: Withdrawing address record for fe80::ea40:f2ff:fee2:4d86 on eth0. Dec 1 13:53:16 andromeda avahi-daemon[890]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::ea40:f2ff:fee2:4d86. Dec 1 13:53:16 andromeda avahi-daemon[890]: Interface eth0.IPv6 no longer relevant for mDNS. Dec 1 13:53:16 andromeda kernel: [ 1069.025288] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready Dec 1 13:53:16 andromeda avahi-daemon[890]: Withdrawing address record for 192.168.11.17 on eth0. Dec 1 13:53:16 andromeda avahi-daemon[890]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.11.17. Dec 1 13:53:16 andromeda avahi-daemon[890]: Interface eth0.IPv4 no longer relevant for mDNS. Dec 1 13:53:16 andromeda NetworkManager[1115]: <warn> DNS: plugin dnsmasq update failed Dec 1 13:53:16 andromeda NetworkManager[1115]: <info> ((null)): removing resolv.conf from /sbin/resolvconf Dec 1 13:53:16 andromeda dnsmasq[1907]: setting upstream servers from DBus Dec 1 13:53:16 andromeda dbus[800]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Dec 1 13:53:16 andromeda dbus[800]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): carrier now ON (device state 20) Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40] Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Auto-activating connection '82579V'. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) starting connection '82579V' Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Dec 1 13:53:32 andromeda kernel: [ 1084.938042] e1000e: e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx Dec 1 13:53:32 andromeda kernel: [ 1084.938049] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO Dec 1 13:53:32 andromeda kernel: [ 1084.938815] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> dhclient started with pid 6080 Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Dec 1 13:53:32 andromeda dhclient: Internet Systems Consortium DHCP Client 4.2.4 Dec 1 13:53:32 andromeda dhclient: Copyright 2004-2012 Internet Systems Consortium. Dec 1 13:53:32 andromeda dhclient: All rights reserved. Dec 1 13:53:32 andromeda dhclient: For info, please visit https://www.isc.org/software/dhcp/ Dec 1 13:53:32 andromeda dhclient: Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): DHCPv4 state changed nbi -> preinit Dec 1 13:53:32 andromeda dhclient: Listening on LPF/eth0/e8:40:f2:e2:4d:86 Dec 1 13:53:32 andromeda dhclient: Sending on LPF/eth0/e8:40:f2:e2:4d:86 Dec 1 13:53:32 andromeda dhclient: Sending on Socket/fallback Dec 1 13:53:32 andromeda dhclient: DHCPREQUEST of 192.168.11.17 on eth0 to 255.255.255.255 port 67 Dec 1 13:53:32 andromeda dhclient: DHCPACK of 192.168.11.17 from 192.168.11.1 Dec 1 13:53:32 andromeda dhclient: bound to 192.168.11.17 -- renewal in 33576 seconds. Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> (eth0): DHCPv4 state changed preinit -> reboot Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> address 192.168.11.17 Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> prefix 24 (255.255.255.0) Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> gateway 192.168.11.1 Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> hostname 'andromeda' Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> nameserver '192.168.11.1' Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> domain name 'hsd1.ca.comcast.net' Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Dec 1 13:53:32 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Dec 1 13:53:32 andromeda avahi-daemon[890]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.11.17. Dec 1 13:53:32 andromeda avahi-daemon[890]: New relevant interface eth0.IPv4 for mDNS. Dec 1 13:53:32 andromeda avahi-daemon[890]: Registering new address record for 192.168.11.17 on eth0.IPv4. Dec 1 13:53:33 andromeda NetworkManager[1115]: <info> (eth0): device state change: ip-config -> activated (reason 'none') [70 100 0] Dec 1 13:53:33 andromeda NetworkManager[1115]: <info> ((null)): writing resolv.conf to /sbin/resolvconf Dec 1 13:53:33 andromeda dnsmasq[1907]: setting upstream servers from DBus Dec 1 13:53:33 andromeda dnsmasq[1907]: using nameserver 192.168.11.1#53 Dec 1 13:53:33 andromeda NetworkManager[1115]: <info> Policy set '82579V' (eth0) as default for IPv4 routing and DNS. Dec 1 13:53:33 andromeda NetworkManager[1115]: <info> Activation (eth0) successful, device activated. Dec 1 13:53:33 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Dec 1 13:53:33 andromeda dbus[800]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Dec 1 13:53:33 andromeda dbus[800]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Dec 1 13:53:33 andromeda avahi-daemon[890]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::ea40:f2ff:fee2:4d86. Dec 1 13:53:33 andromeda avahi-daemon[890]: New relevant interface eth0.IPv6 for mDNS. Dec 1 13:53:33 andromeda avahi-daemon[890]: Registering new address record for fe80::ea40:f2ff:fee2:4d86 on eth0.*. Dec 1 13:53:41 andromeda ntpdate[6154]: adjust time server 91.189.94.4 offset 0.000928 sec Dec 1 13:53:50 andromeda NetworkManager[1115]: <info> (eth0): carrier now OFF (device state 100, deferring action for 4 seconds) Dec 1 13:53:50 andromeda kernel: [ 1102.980003] e1000e: e1000e: eth0 NIC Link is Down Dec 1 13:53:54 andromeda NetworkManager[1115]: <info> (eth0): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40] Dec 1 13:53:54 andromeda NetworkManager[1115]: <info> (eth0): deactivating device (reason 'carrier-changed') [40] Dec 1 13:53:54 andromeda NetworkManager[1115]: <info> (eth0): canceled DHCP transaction, DHCP client pid 6080 Dec 1 13:53:54 andromeda avahi-daemon[890]: Withdrawing address record for fe80::ea40:f2ff:fee2:4d86 on eth0. Dec 1 13:53:54 andromeda avahi-daemon[890]: Leaving mDNS multicast group on interface eth0.IPv6 with address fe80::ea40:f2ff:fee2:4d86. Dec 1 13:53:54 andromeda avahi-daemon[890]: Interface eth0.IPv6 no longer relevant for mDNS. Dec 1 13:53:54 andromeda avahi-daemon[890]: Withdrawing address record for 192.168.11.17 on eth0. Dec 1 13:53:54 andromeda avahi-daemon[890]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.11.17. Dec 1 13:53:54 andromeda kernel: [ 1107.025959] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready Dec 1 13:53:54 andromeda NetworkManager[1115]: <warn> DNS: plugin dnsmasq update failed Dec 1 13:53:54 andromeda NetworkManager[1115]: <info> ((null)): removing resolv.conf from /sbin/resolvconf Dec 1 13:53:54 andromeda avahi-daemon[890]: Interface eth0.IPv4 no longer relevant for mDNS. Dec 1 13:53:54 andromeda dnsmasq[1907]: setting upstream servers from DBus Dec 1 13:53:54 andromeda dbus[800]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Dec 1 13:53:54 andromeda dbus[800]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): carrier now ON (device state 20) Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40] Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Auto-activating connection '82579V'. Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) starting connection '82579V' Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete. Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0] Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful. Dec 1 13:54:10 andromeda kernel: [ 1123.167668] e1000e: e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx Dec 1 13:54:10 andromeda kernel: [ 1123.167675] e1000e 0000:00:19.0: eth0: 10/100 speed: disabling TSO Dec 1 13:54:10 andromeda kernel: [ 1123.168430] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled. Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete. Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0] Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds) Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> dhclient started with pid 6212 Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete. Dec 1 13:54:10 andromeda dhclient: Internet Systems Consortium DHCP Client 4.2.4 Dec 1 13:54:10 andromeda dhclient: Copyright 2004-2012 Internet Systems Consortium. Dec 1 13:54:10 andromeda dhclient: All rights reserved. Dec 1 13:54:10 andromeda dhclient: For info, please visit https://www.isc.org/software/dhcp/ Dec 1 13:54:10 andromeda dhclient: Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): DHCPv4 state changed nbi -> preinit Dec 1 13:54:10 andromeda dhclient: Listening on LPF/eth0/e8:40:f2:e2:4d:86 Dec 1 13:54:10 andromeda dhclient: Sending on LPF/eth0/e8:40:f2:e2:4d:86 Dec 1 13:54:10 andromeda dhclient: Sending on Socket/fallback Dec 1 13:54:10 andromeda dhclient: DHCPREQUEST of 192.168.11.17 on eth0 to 255.255.255.255 port 67 Dec 1 13:54:10 andromeda dhclient: DHCPACK of 192.168.11.17 from 192.168.11.1 Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> (eth0): DHCPv4 state changed preinit -> reboot Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> address 192.168.11.17 Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> prefix 24 (255.255.255.0) Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> gateway 192.168.11.1 Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> hostname 'andromeda' Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> nameserver '192.168.11.1' Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> domain name 'hsd1.ca.comcast.net' Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Dec 1 13:54:10 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) started... Dec 1 13:54:10 andromeda avahi-daemon[890]: Joining mDNS multicast group on interface eth0.IPv4 with address 192.168.11.17. Dec 1 13:54:10 andromeda dhclient: bound to 192.168.11.17 -- renewal in 35416 seconds. Dec 1 13:54:10 andromeda avahi-daemon[890]: New relevant interface eth0.IPv4 for mDNS. Dec 1 13:54:10 andromeda avahi-daemon[890]: Registering new address record for 192.168.11.17 on eth0.IPv4. Dec 1 13:54:11 andromeda NetworkManager[1115]: <info> (eth0): device state change: ip-config -> activated (reason 'none') [70 100 0] Dec 1 13:54:11 andromeda NetworkManager[1115]: <info> ((null)): writing resolv.conf to /sbin/resolvconf Dec 1 13:54:11 andromeda dnsmasq[1907]: setting upstream servers from DBus Dec 1 13:54:11 andromeda dnsmasq[1907]: using nameserver 192.168.11.1#53 Dec 1 13:54:11 andromeda NetworkManager[1115]: <info> Policy set '82579V' (eth0) as default for IPv4 routing and DNS. Dec 1 13:54:11 andromeda NetworkManager[1115]: <info> Activation (eth0) successful, device activated. Dec 1 13:54:11 andromeda NetworkManager[1115]: <info> Activation (eth0) Stage 5 of 5 (IPv4 Commit) complete. Dec 1 13:54:11 andromeda dbus[800]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Dec 1 13:54:11 andromeda dbus[800]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' Dec 1 13:54:12 andromeda avahi-daemon[890]: Joining mDNS multicast group on interface eth0.IPv6 with address fe80::ea40:f2ff:fee2:4d86. Dec 1 13:54:12 andromeda avahi-daemon[890]: New relevant interface eth0.IPv6 for mDNS. Dec 1 13:54:12 andromeda avahi-daemon[890]: Registering new address record for fe80::ea40:f2ff:fee2:4d86 on eth0.*. Dec 1 13:54:19 andromeda ntpdate[6286]: adjust time server 91.189.94.4 offset 0.001142 sec $ lspci -v 00:19.0 Ethernet controller: Intel Corporation 82579V Gigabit Network Connection (rev 04) Subsystem: Intel Corporation Device 2031 Flags: bus master, fast devsel, latency 0, IRQ 45 Memory at f7f00000 (32-bit, non-prefetchable) [size=128K] Memory at f7f39000 (32-bit, non-prefetchable) [size=4K] I/O ports at f040 [size=32] Capabilities: [c8] Power Management version 2 Capabilities: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [e0] PCI Advanced Features Kernel driver in use: e1000e Kernel modules: e1000e $ modinfo e1000e filename: /lib/modules/3.5.0-19-generic/kernel/drivers/net/e1000e/e1000e.ko version: 2.1.4-NAPI license: GPL description: Intel(R) PRO/1000 Network Driver author: Intel Corporation, <[email protected]> srcversion: 0809529BE0BBC44883956AF alias: pci:v00008086d0000153Bsv*sd*bc*sc*i* alias: pci:v00008086d0000153Asv*sd*bc*sc*i* alias: pci:v00008086d00001503sv*sd*bc*sc*i* alias: pci:v00008086d00001502sv*sd*bc*sc*i* alias: pci:v00008086d000010F0sv*sd*bc*sc*i* alias: pci:v00008086d000010EFsv*sd*bc*sc*i* alias: pci:v00008086d000010EBsv*sd*bc*sc*i* alias: pci:v00008086d000010EAsv*sd*bc*sc*i* alias: pci:v00008086d00001525sv*sd*bc*sc*i* alias: pci:v00008086d000010DFsv*sd*bc*sc*i* alias: pci:v00008086d000010DEsv*sd*bc*sc*i* alias: pci:v00008086d000010CEsv*sd*bc*sc*i* alias: pci:v00008086d000010CDsv*sd*bc*sc*i* alias: pci:v00008086d000010CCsv*sd*bc*sc*i* alias: pci:v00008086d000010CBsv*sd*bc*sc*i* alias: pci:v00008086d000010F5sv*sd*bc*sc*i* alias: pci:v00008086d000010BFsv*sd*bc*sc*i* alias: pci:v00008086d000010E5sv*sd*bc*sc*i* alias: pci:v00008086d0000294Csv*sd*bc*sc*i* alias: pci:v00008086d000010BDsv*sd*bc*sc*i* alias: pci:v00008086d000010C3sv*sd*bc*sc*i* alias: pci:v00008086d000010C2sv*sd*bc*sc*i* alias: pci:v00008086d000010C0sv*sd*bc*sc*i* alias: pci:v00008086d00001501sv*sd*bc*sc*i* alias: pci:v00008086d00001049sv*sd*bc*sc*i* alias: pci:v00008086d0000104Dsv*sd*bc*sc*i* alias: pci:v00008086d0000104Bsv*sd*bc*sc*i* alias: pci:v00008086d0000104Asv*sd*bc*sc*i* alias: pci:v00008086d000010C4sv*sd*bc*sc*i* alias: pci:v00008086d000010C5sv*sd*bc*sc*i* alias: pci:v00008086d0000104Csv*sd*bc*sc*i* alias: pci:v00008086d000010BBsv*sd*bc*sc*i* alias: pci:v00008086d00001098sv*sd*bc*sc*i* alias: pci:v00008086d000010BAsv*sd*bc*sc*i* alias: pci:v00008086d00001096sv*sd*bc*sc*i* alias: pci:v00008086d0000150Csv*sd*bc*sc*i* alias: pci:v00008086d000010F6sv*sd*bc*sc*i* alias: pci:v00008086d000010D3sv*sd*bc*sc*i* alias: pci:v00008086d0000109Asv*sd*bc*sc*i* alias: pci:v00008086d0000108Csv*sd*bc*sc*i* alias: pci:v00008086d0000108Bsv*sd*bc*sc*i* alias: pci:v00008086d0000107Fsv*sd*bc*sc*i* alias: pci:v00008086d0000107Esv*sd*bc*sc*i* alias: pci:v00008086d0000107Dsv*sd*bc*sc*i* alias: pci:v00008086d000010B9sv*sd*bc*sc*i* alias: pci:v00008086d000010D5sv*sd*bc*sc*i* alias: pci:v00008086d000010DAsv*sd*bc*sc*i* alias: pci:v00008086d000010D9sv*sd*bc*sc*i* alias: pci:v00008086d00001060sv*sd*bc*sc*i* alias: pci:v00008086d000010A5sv*sd*bc*sc*i* alias: pci:v00008086d000010BCsv*sd*bc*sc*i* alias: pci:v00008086d000010A4sv*sd*bc*sc*i* alias: pci:v00008086d0000105Fsv*sd*bc*sc*i* alias: pci:v00008086d0000105Esv*sd*bc*sc*i* depends: vermagic: 3.5.0-19-generic SMP mod_unload modversions parm: copybreak:Maximum size of packet that is copied to a new buffer on receive (uint) parm: TxIntDelay:Transmit Interrupt Delay (array of int) parm: TxAbsIntDelay:Transmit Absolute Interrupt Delay (array of int) parm: RxIntDelay:Receive Interrupt Delay (array of int) parm: RxAbsIntDelay:Receive Absolute Interrupt Delay (array of int) parm: InterruptThrottleRate:Interrupt Throttling Rate (array of int) parm: IntMode:Interrupt Mode (array of int) parm: SmartPowerDownEnable:Enable PHY smart power down (array of int) parm: KumeranLockLoss:Enable Kumeran lock loss workaround (array of int) parm: CrcStripping:Enable CRC Stripping, disable if your BMC needs the CRC (array of int) parm: EEE:Enable/disable on parts that support the feature (array of int) parm: Node:[ROUTING] Node to allocate memory on, default -1 (array of int) parm: debug:Debug level (0=none,...,16=all) (int)

  Read the article

• WCF timeout exception detailed investigation

  - by Jason Kealey

  We have an application that has a WCF service (*.svc) running on IIS7 and various clients querying the service. The server is running Win 2008 Server. The clients are running either Windows 2008 Server or Windows 2003 server. I am getting the following exception, which I have seen can in fact be related to a large number of potential WCF issues. System.TimeoutException: The request channel timed out while waiting for a reply after 00:00:59.9320000. Increase the timeout value passed to the call to Request or increase the SendTimeout value on the Binding. The time allotted to this operation may have been a portion of a longer timeout. ---> System.TimeoutException: The HTTP request to 'http://www.domain.com/WebServices/myservice.svc/gzip' has exceeded the allotted timeout of 00:01:00. The time allotted to this operation may have been a portion of a longer timeout. I have increased the timeout to 30min and the error still occurred. This tells me that something else is at play, because the quantity of data could never take 30min to upload or download. The error comes and goes. At the moment, it is more frequent. It does not seem to matter if I have 3 clients running simultaneously or 100, it still occurs once in a while. Most of the time, there are no timeouts but I still get a few per hour. The error comes from any of the methods that are invoked. One of these methods does not have parameters and returns a bit of data. Another takes in lots of data as a parameter but executes asynchronously. The errors always originate from the client and never reference any code on the server in the stack trace. It always ends with: at System.Net.HttpWebRequest.GetResponse() at System.ServiceModel.Channels.HttpChannelFactory.HttpRequestChannel.HttpChannelRequest.WaitForReply(TimeSpan timeout) On the server: I've tried (and currently have) the following binding settings: maxBufferSize="2147483647" maxReceivedMessageSize="2147483647" maxBufferPoolSize="2147483647" It does not seem to have an impact. I've tried (and currently have) the following throttling settings: <serviceThrottling maxConcurrentCalls="1500" maxConcurrentInstances="1500" maxConcurrentSessions="1500"/> It does not seem to have an impact. I currently have the following settings for the WCF service. [ServiceBehavior(InstanceContextMode = InstanceContextMode.Single, ConcurrencyMode = ConcurrencyMode.Single)] I ran with ConcurrencyMode.Multiple for a while, and the error still occurred. I've tried restarting IIS, restarting my underlying SQL Server, restarting the machine. All of these don't seem to have an impact. I've tried disabling the Windows firewall. It does not seem to have an impact. On the client, I have these settings: maxReceivedMessageSize="2147483647" <system.net> <connectionManagement> <add address="*" maxconnection="16"/> </connectionManagement> </system.net> My client closes its connections: var client = new MyClient(); try { return client.GetConfigurationOptions(); } finally { client.Close(); } I have changed the registry settings to allow more outgoing connections: MaxConnectionsPerServer=24, MaxConnectionsPer1_0Server=32. I have now just recently tried SvcTraceViewer.exe. I managed to catch one exception on the client end. I see that its duration is 1 minute. Looking at the server side trace, I can see that the server is not aware of this exception. The maximum duration I can see is 10 seconds. I have looked at active database connections using exec sp_who on the server. I only have a few (2-3). I have looked at TCP connections from one client using TCPview. It usually is around 2-3 and I have seen up to 5 or 6. Simply put, I am stumped. I have tried everything I could find, and must be missing something very simple that a WCF expert would be able to see. It is my gut feeling that something is blocking my clients at the low-level (TCP), before the server actually receives the message and/or that something is queuing the messages at the server level and never letting them process. If you have any performance counters I should look at, please let me know. (please indicate what values are bad, as some of these counters are hard to decypher). Also, how could I log the WCF message size? Finally, are there any tools our there that would allow me to test how many connections I can establish between my client and server (independently from my application) Thanks for your time! Extra information added June 20th: My WCF application does something similar to the following. while (true) { Step1GetConfigurationSettingsFromServerViaWCF(); // can change between calls Step2GetWorkUnitFromServerViaWCF(); DoWorkLocally(); // takes 5-15minutes. Step3SendBackResultsToServerViaWCF(); } Using WireShark, I did see that when the error occurs, I have a five TCP retransmissions followed by a TCP reset later on. My guess is the RST is coming from WCF killing the connection. The exception report I get is from Step3 timing out. I discovered this by looking at the tcp stream "tcp.stream eq 192". I then expanded my filter to "tcp.stream eq 192 and http and http.request.method eq POST" and saw 6 POSTs during this stream. This seemed odd, so I checked with another stream such as tcp.stream eq 100. I had three POSTs, which seems a bit more normal because I am doing three calls. However, I do close my connection after every WCF call, so I would have expected one call per stream (but I don't know much about TCP). Investigating a bit more, I dumped the http packet load to disk to look at what these six calls where. 1) Step3 2) Step1 3) Step2 4) Step3 - corrupted 5) Step1 6) Step2 My guess is two concurrent clients are using the same connection, that is why I saw duplicates. However, I still have a few more issues that I can't comprehend: a) Why is the packet corrupted? Random network fluke - maybe? The load is gzipped using this sample code: http://msdn.microsoft.com/en-us/library/ms751458.aspx - Could the code be buggy once in a while when used concurrently? I should test without the gzip library. b) Why would I see step 1 & step 2 running AFTER the corrupted operation timed out? It seems to me as if these operations should not have occurred. Maybe I am not looking at the right stream because my understanding of TCP is flawed. I have other streams that occur at the same time. I should investigate other streams - a quick glance at streams 190-194 show that the Step3 POST have proper payload data (not corrupted). Pushing me to look at the gzip library again.

  Read the article

< Previous Page | 3 4 5 6 7